JPH0320186A - Opposed valve seat type solenoid on-off valve - Google Patents

Abstract

PURPOSE:To enable it to perform smooth valve opening at all times by partitioning off a pressure chamber in surrounding the back of at least one side of valve bodies with a flexible diaphragm, and forming a through hole interconnecting both sides of the valve. CONSTITUTION:When excitation of a solenoid 14 is released, vertical valve bodies 10, 11 come into contact with valve seats 8, 9 by dint of elastic expanding force of respective coil springs 12, 13 and they are closed. At this time, even if pressure in a valve space chamber 5 closed by the valve bodies 10, 11 by a cause of variations in ambient temperature or the like comes to negative pressure, the upper valve body 10 passes a through 32 and the lower valve body 11 passes a through hole 27 whereby respective pressure chambers 29, 31 are interconnected to the valve space chamber 5 and come to the same pressure, so that force acting both sides of each of these valve bodies 10, 11 comes almost the same, thus any force preventing valve opening will not work any longer. Consequently, with excitation of the solenoid 14, these valve bodies 10, 11 can be easily opened or closed against resiliency of the coil springs 12, 13.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an opening to the inflow passage and an opening to the outflow passage which are opposed to each other in a valve chamber formed between an inflow passage and an outflow passage in a body. A valve seat is formed in each of the valves, and the valve is closed by bringing the two valve bodies into contact with both valve seats from the inlet passage side and the outlet passage side by the biasing force of the valve closing spring, and the electromagnetic attraction force due to the excitation of the solenoid is applied. This invention relates to an opposed valve seat type electromagnetic on-off valve which opens by separating both valve bodies from both valve seats.

Problems to be Solved by the Prior Art and the Invention In the above-mentioned opposed valve seat type electromagnetic on-off valve, when the temperature fluctuates in the valve closed state, the inside of the intervalve chamber sealed by both valve bodies,
As the internal pressure increases as the temperature rises, the valve on the outflow path side opens and fluid flows out into the outflow path.
After this, as the temperature decreases, the fluid in the valve chamber contracts and the internal pressure becomes lower than the pressure in the outflow passage. Negative pressure also acts on a force in the valve closing direction, and in this state, even if the solenoid generates an electromagnetic attraction force in the valve opening direction, the valve body remains in close contact with the valve seat and the valve cannot open. Sometimes it disappeared. Means for Solving the Problems The present invention, as a means for solving such problems, surrounds the back surface of at least one valve body with a flexible diaphragm such as a bellows to define a pressure chamber. It has a configuration in which a vent hole is formed that communicates between the front side and the back side of the valve body.

Effects and Effects of the Invention The present invention has the above configuration, and even if the pressure in the valve chamber decreases below the pressure in the outflow path due to temperature fluctuations, the pressure chamber on the back surface of at least one valve body is maintained in the valve chamber by the through hole. Since the valve element is in communication with the valve seat and has the same pressure, the valve element is not attracted to the valve seat, and the valve opens against the elasticity of the valve closing spring due to the attraction force generated by the excitation of the solenoid. When the valve is opened, the negative pressure in the valve chamber is eliminated, so the other valve body is also opened by the excitation of the solenoid, and the negative pressure in the valve chamber causes the valve body to come into close contact with the valve seat, causing the valve to open. There is no difficulty in opening the valve, and the effect is that the valve can always be opened smoothly.

Example Embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1 showing the first embodiment, l is a body in which an inflow passage 2 and an outflow passage 3 are formed that are open on both left and right sides, and the horizontal part of a partition wall 4 that partitions both flow passages 2 and 3 is An intervalve chamber 5 is formed by penetrating the valve in the direction, and an upper valve port 6 communicating with the inflow path 2 and a lower valve port 7 communicating with the outflow path 3 are formed in the four valve chambers 5. Above and below the intervalve chamber 5, the valve ports 6 and 7 are closed by approaching each other and abutting the valve seats 8 and 9 of each valve port 6 and 7 from the inflow path 2 side or the outflow path 3 side. Two valve bodies IO and II are mounted in a state where they are biased in the valve-closing direction by valve-closing compression coil springs 12 and I3, respectively.

On the upper surface of the body l, there are I coils I7 wound around a bobbin l5 having a center hole l6 in the vertical direction, a core l8 fixed at a central position in the center hole l6 of the bobbin l5, and this core. A solenoid I4 consisting of two plungers I9 and 20 that are slidably fitted on both the upper and lower sides of the lower plunger 20 is fixed, and the lower end facing into the inflow passage 2 of the lower plunger 20 has the above-mentioned upper The valve body IO is fitted onto the outside, and a flange 2l formed at the lower end of the plunger 20 prevents the valve body IO from being pulled out from the plunger 20 downwardly. Valve rod 2 passing through the center hole 23 of the lower plunger 20
The upper end of the plunger 2 is in contact with the lower surface of the upper plunger l9, and the lower end of the plunger l9 is in contact with the lower valve body I.
It is in contact with I. The lower valve body 11 has an abutment body 2 in the center.
4 is fitted, this abutting body 24 has a split elbow 25 and a recess 26 formed on the upper surface, the lower end of the plunger l9 is fitted into the hollow 26, and a through hole 27 connected to the split elbow 25 is formed in the center. A bellows 28 is integrally formed on the back surface of the valve body I1, the lower end of which is hermetically fixed to the bottom plate of the body I, and a pressure chamber 29 is defined on the back surface of the valve body 11. .

A bellows 30 is also integrally formed on the back surface of the upper valve element IO, and its upper end is hermetically fixed to the upper plate of the body 1, defining a pressure chamber 31. 3
A through hole 32 is formed to communicate with the surface side.

Next, the operation of this embodiment will be explained. Energize coil 17 and activate the solenoid! When 4 is excited, the upper and lower plungers 19
, 20 is sucked into the core l8, and the upper valve body! 0 is pulled up by the lower plunger 20, and the lower valve body 11 is pushed by the upper plunger 19 through the valve rod 22, thereby separating from the valve seats 8 and 9 and opening the valves. When the solenoid I4 is de-energized, the upper and lower valve bodies lO and 11 contact the valve seats 8 and 9 due to the elastic expansion forces of the coil springs l2 and l3, respectively, and close the valve, as shown by chain lines in the figure.

At this time, due to factors such as temperature fluctuations, the valve body lO, 11
Even if the pressure in the intervalve chamber 5 becomes negative or positive, the upper valve element 10 passes through the through hole 32, and the lower valve element 11 through the through hole 27, allowing the respective pressure chambers 29, 3I to Since they are in communication with the valve chamber 5 and have the same pressure, the forces acting on the front and back surfaces of each valve body 10 and 1l are approximately the same, so that no force that prevents the valve from opening acts, and the solenoid 14 is energized. As already mentioned, each valve body lO, 11 is a coil spring 12, ! It opens and closes against the elasticity of step 3. Here, in order to equalize the force acting on the front and back surfaces of each valve body 10, 1, it is desirable that the effective pressure receiving area of each back surface be the same as that of the valve ports 6, 7. In this embodiment, the coil I7 may be divided into two parts, upper and lower.

The second embodiment shown in FIG. 2 has two solenoids 35, upper and lower.
, 36 are energized, the plungers 37 and 38 are attracted separately, and the valve bodies 39 and 40 are actuated in the valve opening direction. When the valve is closed, the back surfaces of the valve bodies 39 and 40 are surrounded by the bellows 4I142, and the pressure chambers 47 and 48 are closed.
are defined, and each pressure chamber 47, 48 communicates with the surface through a through hole 43, 44, and an intervalve chamber 49 is defined in the valve closed state.
The pressure becomes the same as that of the pressure chambers 47 and 48, and the valve opens easily, and the effect is the same as that of the first embodiment. Note that the bellows 41, 42 and the through holes 43, 44 may be provided only in one of the valve bodies 39, 40.

[Brief explanation of the drawing]

FIG. 2 is a sectional view of the eleventh second embodiment of the present invention. ■: Body 2: Inflow path 3: Outflow path 5, 49: Valve chamber 6, 7: Valve port 8, 9: Valve seat IO, 11, 39,
40: Valve body! 2, l3, 45, 46: Coil spring I
4, 35, 36: Solenoid 19, 20, 37, 38
: Blunger 27, 32, 43, 44: Through hole 28,
30, 41.42: Bellows 29, 31, 47, 48
:Pressure chamber

Claims (1)

[Scope of Claims] A valve seat is formed at an opening to the inflow passage and an opening to the outflow passage, which are opposed to each other in an intervalve chamber formed between an inflow passage and an outflow passage in the body. The valve is closed by bringing the two valve bodies into contact with the valve seats from the inlet passage side and the outlet passage side by the biasing force of the valve-closing spring, and the valve is closed by the electromagnetic attraction force generated by the excitation of the solenoid. In the opposed valve seat type electromagnetic on-off valve that opens by separating the valve bodies from the valve seats, the back surface of at least one of the valve bodies is surrounded by a flexible diaphragm such as a bellows to form a pressure chamber. An opposed valve seat type electromagnetic on-off valve characterized by forming a through hole that communicates between the front side and the back side of the valve body.